Children 9 to 30 months with weights for age and gender below the fifth per-centile are seen for medical and nutritional evaluation in the CCRC. As part of the larger federally funded project, these children and their mothers are seen for behavioral observations to be correlated with data on the time course of adrenocortical activity. Children 9 to 30 months with weights for age and gender below the fifth per-centile are seen for medical and nutritional evaluation in the CCRC. As part of the larger federally funded project, these children and their mothers are seen for behavioral observations to be correlated with data on the time course of adrenocortical activity.